A metal organic chemical vapor deposition method (MOCVD method) has been employed for the crystal growth of a nitride semiconductor as frequently as a molecular beam epitaxy method (MBE method). In particular, the MOCVD method has been widely employed in apparatuses for the mass production of compound semiconductors in the industrial community because the method provides a higher crystal growth rate than the MBE method does and obviates the need for a high-vacuum apparatus or the like unlike the MBE method. In recent years, in association with widespread use of blue or ultraviolet LEDs and of blue or ultraviolet laser diodes, numerous researches have been conducted on increases in apertures and number of substrates each serving as an object of the MOCVD method in order that the mass productivity of gallium nitride, gallium indium nitride, and gallium aluminum nitride may be improved.
Such vapor phase epitaxy apparatuses are, for example, vapor phase epitaxy apparatuses each having a susceptor for holding a substrate, an opposite face of the susceptor, a heater for heating the substrate, a reactor formed of a gap between the susceptor and the opposite face of the susceptor, a raw material gas-introducing portion for supplying a raw material gas from the central portion of the reactor toward the peripheral portion of the reactor, and a reacted gas-discharging portion as described in Patent Documents 1 to 4. Each of those vapor phase epitaxy apparatuses is of such a constitution that a plurality of substrate holders are provided for the susceptor and the substrate holders each rotate and revolve in association with the rotation of the susceptor by driving means. Further, two kinds of forms, i.e., a form in which a crystal growth surface is directed upward (face-up type) and a form in which a crystal growth surface is directed downward (face-down type) have been mainly proposed as a form of a vapor phase epitaxy apparatus.    [Patent Document 1] JP 2002-175992 A    [Patent Document 2] JP 2006-253244 A    [Patent Document 3] JP 2007-96280 A    [Patent Document 4] JP 2007-243060 A    [Patent Document 5] JP 2002-246323 A